Experimental Analysis of Shale for Evaluating Shale Drilling Fluid Interaction in Agbada Formation

Aims: To characterize the shale samples from Agbada formation and to develop an inhibitive water-based mud for the shale types. Study Design: Experimental. Place and Duration of Study: Department of Petroleum, University of Port Harcourt Rivers State, Agbada Formation Niger-Delta Region, between March 2011 and August 2012. Methodology: This study includes the determination of shale properties such as mineralogy, cation exchange capacity, native moisture content and total organic carbon content of the shale samples collected from two wells in Agbada Field. It also involves the establishment of an adsorption isotherm for the shale and the modeling of these isotherms using the Guggenheim, Anderson and Deboer model. Results: Based on the results of the dispersion and swelling tests, 3% Bentonite + 1% Potassium Chloride (KCl) were selected as the promising fluid. Well A exhibited the Type II isotherm which is common to most shale while Well B showed the Type V isotherm. Adsorption isotherm model predictions were in agreement with experimental observations. The samples from the wells exhibited dispersion after testing with deionized water. For Well A and B, 3% Bentonite + 1% Potassium Chloride (KCl) inhibits and yielded higher shale percent recovery values from dispersion tests. Conclusion: It was observed from adsorption isotherm models that the total organic carbon content is not a significant factor in the adsorptive and dispersive behaviors exhibited by the shale samples

Effect of Reversible Invert Emulsion Fluid Additives on The Environment – An Environmental Concern During Drilling Operation

The effect of reversible invert emulsion drilling fluid additives on the soil has been examined in order to evaluate their toxicity and possible environmental impacts that may result from their indiscriminate disposal. Development of effective policies for discharges depends on consideration of the specific local environmental conditions that govern the fate of discharge materials, the scientific basis for assessing the potential for effects in that environment, and balanced consideration of the environmental effects and relative costs of discharge versus other disposal options. This paper reviews the framework that will help achieve general regulatory acceptance of the discharge of reversible invert emulsion mud. In this study, the contaminated soil samples were collected and analysed for metals (iron, copper, zinc, lead, nickel, chromium, manganese, calcium and magnesium) using Atomic Absorption Spectrophotometry (AAS) method. The results showed that Calcium (Ca) has the highest concentration followed by Iron (Fe), Copper (Cu) with varying level of toxic metals like lead (Pb), Nickel (Ni), Manganese (Mn) and Chromium (Cr) in the soil sample. Metals like Fe, Mn and Cu generally have values higher than that of the United States Environmental Protection Agency and World Health Organization Standards thereby implying possible negative impacts on the immediate environments. It is therefore recommended that wastes resulting from oil cuttings and drilling muds should be properly treated before it is disposed into the environment by oil exploration companies

Economic Viability of the Use of Local Pseudo-Oils for Drilling Fluid Formulation

The initial cost of formulating Synthetic Base Muds (SBM) compared to conventional Oil Base Muds (OBM) may be doubled but after considering the cost of containment, hauling, and disposal of OBM after use, the cost of using SBM becomes relatively cheaper. The formulation and disposal options (onshore and offshore) and the cost benefit of using seven local antioxidated pseudo-oils (vegetable esters) SBM compared to commercial OBM at an average offshore and onshore temperature operations were simulated in this work using API standard performance benchmarks. The average cost percent of savings on the use of the seven local vegetable oils over the use of commercial synthetic base fluid offshore and onshore were 48.32% and 56.30% respectively. Thus the use of local ester oils for drilling fluids formulation are more economical compared to currently imported oil based drilling fluids. The cultivation and production of these local pseudo-oils are on the increase guaranteeing its adoption and application to be very sustainable.Keywords: Antioxidants, Disposals, Economics, Esters, Formulation

A Rare Case of Nonsecretory Multiple Myeloma in Lagos, Nigeria: A Case Report and Literature Review

Multiple myeloma (MM) is a plasma cell disorder associated with clonal proliferation of plasma cells. Nonsecretory multiple myeloma (NSMM) is a rare variant of MM and accounts for approximately 1% to 5% of all cases. It is defined as symptomatic myeloma without detectable monoclonal immunoglobulin on serum or urine electrophoresis. This variant usually poses a diagnostic challenge to the clinician. We present a 60-year-old Nigerian man who was investigated extensively for bone pain, weight loss, and anaemia. He was eventually diagnosed as having nonsecretory multiple myeloma based on histology and immunohistochemistry results of bone marrow trephine biopsy. He is currently being managed with bortezomib, doxorubicin, and thalidomide, as well as zoledronic acid. He is also on anticoagulation. He continues to show remarkable clinical improvement. We describe this case report and literature review for better awareness amongst medical practitioners and pathologists

Factors influencing CD4 cell count in HIV-positive pregnant women in a secondary health center in lagos, nigeria

Background: Immunity in pregnancy is physiologically compromised, and this may affect CD4 count levels. It is well-established that several factors affect CD4 count level in pregnancy. This study aimed to determine the mean and reference range of CD4 count in human immunodeficiency virus (HIV)-positive pregnant women in Lagos, Nigeria. Methods: A retrospective study was carried out at antenatal clinics of the Maternal and Child Center of a secondary health center in Lagos State, Nigeria. Records of HIV-positive pregnant women at various gestational ages, including CD4+ cell count at booking, packed cell volume (PCV) at booking and labor, gestational age at delivery, and infant weight and sex were retrieved. The descriptive data was given as mean ± standard deviation (SD). Pearson's chi-squared test and correlation were used for analytical assessment. Results: Data were retrieved for a total of 143 patients. The mean age was 31.15±3.78 years. The mean PCV was 31.01%±3.79% at booking and 30.49%±4.80% during labor. The mean CD4 count was 413.87±212.09 cells/µL, with a range of 40 to 1,252 cells/µL. The mean infant weight was 3.05±0.45 kg, with a range of 2 to 5 kg. Age of the mother, gestational age, and PCV at booking were not statistically significantly associated with CD4 count. Conclusion: Maternal age, gestational age, and PCV at booking had no significant effects on CD4+ cell count levels in pregnancy. The mean CD4+ cell count of HIV-positive pregnant women in Lagos is 413.87±212.09 cells/µL

Data on cost analysis of drilling mud displacement during drilling operation

The focus of this research was to present a data article for analyzing the cost of displacing a drilling fluid during the drilling operation. The cost of conventional Spud, KCl and Pseudo Oil base (POBM) muds used in drilling oil and gas wells are compared with that of a Reversible Invert Emulsion Mud.The cost analysis islimited tothree sections for optimum and effective Comparison. To optimize drilling operations, it is important that we specify the yardstick by which drilling performance is measured. The most relevant yardstick is the cost per foot drilled.The datahave shown thatthe prices fordrilling mud systems are a function of the mud system formulation cost for that particular mud weight and maintenance per day. These costs for different mud systems and depend on the base fluid. The Reversible invert emulsion drilling fluid, eliminates the cost acquired in displacing Pseudo Oil Based mud (POBM) from the well, possible formation damage (permeability impairment) resulting from the use of viscous pill in displacing the POBM from the wellbore, and also eliminates the risk of taking a kick during mud change-over. With this reversible mud system, the costs of special fluids that are rarely applied for the well-completion purpose (cleaning of thick mud filter cake) may be reduced to the barest minimum

Quality of sleep in an HIV population on antiretroviral therapy at an urban tertiary centre in Lagos, Nigeria

Aim. To determine the prevalence of sleep disturbance and its associated characteristics in HIV-positive outpatients on HAART using the PSQI. Methods. Using a cross-sectional design, 300 patients attending the outpatient HIV/AIDS clinic at the Lagos State University Teaching Hospital were recruited. Baseline data obtained included the participants’ demographic data, educational qualification, and marital status. Their treatment history, including duration since HIV diagnosis, the most recent CD4 cell count, and current antiretroviral therapies, was obtained from their case records. Each participant completed the PSQI questionnaire and those with scores ≥5 were diagnosed with poor sleep quality. Results. The participants were made up of 70.7% females and 29.3% males. Their ages ranged between 18 and 74 years with a mean of 38.9 ± 10.3 years. According to the PSQI, 59.3% reported poor sleep quality. The mean score of those with poor quality sleep (9.2 ± 3.3) was comparable to that of those with good quality sleep (1.26 ± 1.4). \u1d443 < 0.001. Significant differences were observed in all the individual components of the PSQI (\u1d443 < 0.001). On multivariate analyses, the independent associations with sleep quality were the duration since HIV diagnosis (\u1d443 = 0.29), efavirenz based regimen (\u1d443 < 0.001), and lower CD4 cell count (\u1d443 < 0.001). Conclusions. Sleep disturbances are quite common in the HIV population even in the era of HAART. Early recognition via routine assessment and effective treatments could prevent the resultant complications and improve quality of life

Modelling of Sub-Sea Gas Transmission Pipeline to Predict Insulation Failure

Background: Thermally insulated subsea production and transmission systems are becoming more common in deep-water/ offshore operations. Premature failures of the insulation materials for these gas transmission pipelines have had significant operational impacts. The ability to timely detect these failures within these systems has been a very difficult task for the oil and gas industries. Thus, periodic survey of the subsea transmission systems is the present practice. In addition, a new technology called optic-fibre Distributed Temperature Sensing system (DTS) is now being used to monitor subsea transmission pipeline temperatures; but this technology is rather very expensive. Objective: However, this study proposed a model which will not only predict premature insulation failure in these transmission pipelines; but will also predict the section of the transmission line where the failure had occurred. Methods: From this study, we deduced that in gas pipeline flow, exit temperature for the system increases exponentially with the distance of insulation failure and approaches the normal operation if the failure occurs towards the exit of the gas pipe. This model can also be used to check the readings of an optic-fibre distributed temperature sensors. Result and Conclusion: After developing this model using classical visual basic and excel package, the model was validated by cross plotting the normal temperature profiles of the model and field data; and R-factor of 0.967 was obtained. Analysis of the results obtained from the model showed that insulation failure in subsea gas transmission pipeline can be predicted on a real-time basis by mere reading of the arrival temperature of a gas transmission line

PRODUCTION OF SILICON ETHOXIDE FROM NIGERIAN RICE HUSK

Application of nanotechnology has been very limited in petroleum industry. However, in recent years, the importance of nano science to develop conventional methods in several branches of petroleum engineering has been highlighted. Despite the considerable surveys investigating different applications of nanotechnology in optimizing drilling fluid rheology in HTHP conditions and reservoir engineering (enhanced oil recovery techniques); far too little attention has been paid to producing these nano particles / additives locally in Nigeria. The petroleum industry has been the mainstay of Nigeria economy accounting for more 90% of our gross earning. The Nigerian Oil and Gas Industry Content Development Act 2010 seek to increase indigenous participation in the Oil and gas industry by prescribing minimum thresholds for the use of local services and materials. Due to the high silica content in rice husk, preparation of silica products is considered to be the most attractive utilization method at present. Amorphous silica is a basic raw material, which has found an increasingly wide market in industries. Rice husk is a well-known, abundant agricultural byproduct in rice-producing countries such as Nigeria. The disposal of rice husk has become a great environmental threat to the land and the surrounding areas where it is dumped. Therefore, recycling the waste and producing high-value materials is not only beneficial to the environment but is also a promising bio-resource technology. In this paper, an optimized process for preparation of nanosilica from rice husk is described. The characteristics of the nanosilica prepared are described and the silica content of the nanosilica reached a record of 94% purity in the method adopted. The nanosilica was further processed to form Silicon ethoxide which is an emulsifier that has its application in the industry. It can be deduced from the results that Silicon ethoxide is considered as a reversible surfactant because of it hydrophilic and hydrophobic nature. These chemical nature and functional group plays an important role in performance characteristic of a reversible mud

Development and Testing of Sorption Isotherm Equipment for Nigerian Coal

Aim: The aim of the study is to investigate the methane content in Nigerian coal. Study Design: Fabrication of Sorption Isotherm Equipment and Experimental Analysis. Place and Duration of Study: Department of Petroleum and Gas Engineering, University of Port Harcourt Rivers State, between June, 2014 and January, 2015. Methodology: This study includes the Fabrication of Isotherm Adsorption Equipment, Methane Sorption test, Proximate Analysis, Ultimate Analysis, and Estimation of Methane Content. Results: The maximum moisture and fixed carbon was found in Sample D with moisture content of 3.35%, fixed carbon content of 60.41%; and it also has the minimum ash content of 5.61%. The maximum volatile matter was found in Sample B with volatile matter of 33.57%. The estimated methane content from the Meissner’s method differs from those obtained from the adsorption Isotherm equipment by 22%. Conclusion: The adsorption isotherm models obtained, showed that the total organic carbon content is not a significant factor in the adsorptive and dispersive behaviors exhibited by the shale